


You Smell Like Mine

by bleep0bleep, marguerite_26



Category: Teen Wolf (TV)
Genre: Alpha Derek, Alpha/Beta/Omega Dynamics, Alpha/Omega, Alternate Universe - College/University, M/M, Mates, Mating Cycles/In Heat, Mutual Pining, Omega Stiles Stilinski, Omega Verse, Pining Derek
Language: English
Status: Completed
Published: 2015-11-28
Updated: 2015-11-28
Packaged: 2018-05-03 04:14:49
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 13,420
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5276216
Author URL: https://archiveofourown.org/users/bleep0bleep/pseuds/bleep0bleep, https://archiveofourown.org/users/marguerite_26/pseuds/marguerite_26
Summary: <blockquote class="userstuff">
              <p>People talk about the <i>alpha instinct</i>, an alpha's head being swayed by a nice-smelling omega, or the desire to drop everything and show off. Derek's never felt any of that. He's just not that kind of alpha.</p><p>Then he meets Stiles.</p>
            </blockquote>





	You Smell Like Mine

**Author's Note:**

  * For [blindinglights](https://archiveofourown.org/users/blindinglights/gifts).



> Thanks to F for being a fabulous beta. 
> 
> A Russian translation is available [here!](https://ficbook.net/readfic/6478884)

Derek Hale, after three years of surviving—and loving—the chaos of UCLA student housing, now found himself starting his junior year as the new Resident Advisor for Hedrick Hall's third floor. And it was starting out a bit rocky.

He should be loving every minute of it—for one thing all RAs had the bonus of having their own room. There were no more cramped bunk beds shared with Boyd or crashing at Isaac's when Erica wanted to spend the night; no, this was all Derek's domain, and he loved every square foot of it. So he couldn't quite figure out why he was feeling so _off_.

To change his mood, he took a break from unpacking, and checked the group chat he was in with Boyd, Erica and Isaac. After confirming that "Yes, Isaac, it was the largest dorm room of the third floor," he hinted that once they were done moving into their off-campus apartment they could come over and help with his couch.

Some friendly faces would help with the weird tension making his shoulders ache.

Derek shook his head at Erica's string of emojis and gave up trying to figure out if they meant she was eating ten pizzas or going shopping for groceries. He assumed she was busy, but Boyd and Isaac gave a vague agreement, saying they'd be by after they finished a round of Halo.

Not hopeful they'd be around any time soon, he headed down to pick up his couch from its previous owner, who dropped it off in the loading area and then promptly peaced out to go to a party.

Derek was standing by the couch, trying to figure out how to get it into the elevator by himself, when a good Samaritan came along.

"Need some help with that?" the guy asked. His grin was enthusiastic and sincere. Derek assumed he was a freshman from his youth and also the yet-to-be-jaded-by-college-life demeanor. He held out his hand for Derek to shake. "I'm Scott, by the way."

 _Another Alpha_ , Derek noted with a touch of annoyance, and he squared his shoulders. Then immediately called himself an idiot. He'd never been territorial in his life.

"Derek," he said, shaking off the unexpected need to squeeze Scott's hand with a little extra strength. He nodded to the other end of the couch. "I appreciate the offer." The words came out not sounding appreciative at all.

"No worries, man," Scott said, clearly oblivious to any of Derek's posturing. "I'm going up to see a friend in Hedrick, anyway."

Scott helped Derek haul the thing to the elevator and into his room, chatting about his excitement and worries around starting pre-med. His easy confidence set and humility calmed Derek's momentary need to assert his authority. After they finished with the couch, Derek shook Scott's hand. When he thanked him again, he tried to sound more sincere, but it was difficult to put to rest the weird instincts he was feeling.

As he watched Scott go off to find his friend's room down the hall, Derek chastised himself for having one of those weird alpha moments that he thought people should've gotten over in high school. It wasn't like he'd ever had these moments before—why start now?

He focused again on unpacking. Slowly but surely Derek hauled his prized appliances—a mini fridge, a microwave and a toaster—up to his dorm. Derek had opted out of the full meal plan this year, only going for half, so he was saving quite a bit of money. And there would be no more cramped bunk beds shared with Boyd or crashing at Isaac's when Erica wanted to spend the night; no, this was all Derek's domain, and he loved every square foot of it.

It certainly had been the selling point back in May when he'd been offered the position. He'd almost said no. The fourth year advanced calculus he needed for his Econ major was rumored to be brutal, but his mother had stared him down over Skype and told him to do what his gut said was right for him, instead of what was easy.

It struck him as he caught the distinct scent of an omega walking by his door, that maybe he hadn't made the right decision. For another eight months, he'd be surrounded with the scents of every sort of person under the sun.

And for the first time, it was making his head spin.

The student housing of UCLA had many options, including several 'fully mixed' buildings with male and female, alpha, beta and omega, human and werewolf all living under the same roof. Not many colleges allowed full co-ed living arrangements, but Derek had done his research when applying, and studies had shown that co-habitation improved respect and understanding between genders and classifications.

At eighteen, Derek had been just the sort of idealistic high school senior to think it was a great idea. After all, he'd never understood the so-called 'alpha instinct' and how some people would complain about their hormones being distracting; he'd never had that problem. Sure, he'd presented late, and sometimes omegas smelled nice, but Derek never had the common experience of being _consumed_ by the scent of an omega; Laura had once gotten lost in town because she'd spent the day wandering about in a confused haze.

The ache in his shoulders was only getting worse. And he realized, today, for the first time in years, he was struggling with control.

Everything around him felt a little more intense—the alpha across the hall was setting him on edge. The omega three doors down had Derek shaking himself to keep focused on unpacking. Derek was having trouble concentrating; he looked down at the book in his hand and was unable to decipher the text on the cover. He'd never had a problem like this before, not in all the time he'd lived at Hedrick.

Before he'd left, his mom had mentioned something about taking on leadership roles maybe bringing out his alpha instincts, but he'd shrugged it off as wishful thinking on her part. She'd had Laura and Cora, who both took to being alphas, well, like they were born for it.

It wasn't that Derek minded needing to work at being a strong leader. Having a take-charge attitude, being goal-oriented and good at public speaking—these were the things alphas were supposed to be inherently suited to. Laura was now a high-powered lawyer in New York, and Cora was starting her undergrad at Northwestern with a hefty debate resume under her belt.

Derek had always been the quiet one, didn't have a temper, and considered himself lucky he didn't have to worry about some of the pitfalls of being an alpha either. His ruts were light enough for him to still go to school and work through, and he'd never really understood the mating instinct at all. Sure, he'd been attracted to people; other alphas or betas, and an omega here and there had tempted him, but it had never been that all consuming sort of deal other alphas were always swooning about when they met The One.

Only now, for some reason, Derek had an irrational and totally unacceptable desire to go introduce himself to the unknown omega down the hall. He ignored the urge and hoped this wasn't a sign of things to come.

Had Derek known in May that accepting such a leadership role could trigger the onset of instincts he should have learned to deal with during puberty, he might have told his gut to shut the fuck up.

_Crash._

His door—propped open just a crack, to let students know he was in and available—smashed open, and his friends were making their way through the doorway: one with as much irreverence and bluster as he could manage, the other stoically following behind, quietly amused.

"Derek Hale, RA! Who the hell thought that would be a good idea?" Isaac said, tossing himself on the couch Derek was still trying to find the best location for. Derek rolled his eyes and shoved the couch, with Isaac in it, toward the corner. It actually moved a good few inches further than he expected.

Isaac laughed. "Been working out this summer?"

"Room's bigger than I remember." Boyd looked around, nodding his approval at the cracks and pen marks covering the bare walls. The last RA had covered every inch of wall space with skateboarding posters.

"Hey, guys." Derek raised his eyebrows at Isaac, who promptly got off the couch and helped him pick it up and center it to the back wall. "I wasn't expecting you until later."

"We came early to see if you've made any freshers cry."

Derek took a balled up pair of socks and tossed it at Isaac's head. He cocked his head until his neck cracked, but it did little to alleviate the tension from the nonstop sensory overload that had started when he arrived at the dorm.

Isaac stretched out on his place on the couch again. Derek sighed, knowing Isaac would probably be claiming that spot for the duration of the term.

"Single room, though," Boyd said, grabbing the desk chair and testing it out. Likely to see if it was worth fighting Isaac for the couch. "That's a sweet deal."

"And keys to all the dorms on this floor. Party time." Isaac snatched the envelope of keycards off the nightstand and waved them in the air with a throaty laugh.

Derek's head buzzed with a sudden flare of anger, and he roared, hand springing out to snatch the envelope from Isaac.

"Don't," he snarled, voice nearly feral.

Isaac shrank from him. "Holy. Shit. Dude."

"Uh, Derek." Boyd jumped to stand between them, voice carefully calm. His head bowed slightly in beta-deference, a behavior Derek always thought was textbook and traditionally useless but something about it made his anger quell, and he took a step back.

"Something you want to tell us, man?" Boyd asked.

Derek knew his eyes had flashed red. The fingers that clutched the keys were still clawed, and it took him a moment, three deep breaths, to get them back to normal again. He felt like a snake shedding his old skin, the new one tender and raw. That image was disturbing enough to only make him feel worse.

It hadn't occurred to him until now that his relationship with his friends might be tested over this.

"It's been happening all day," Derek said, crashing to his bed, hands buried in his hair. "Not this, exactly. Just, I don't know... _alpha_ stuff."

Alpha stuff wasn't something they ever talked about. They'd been friends since freshman year. Boyd and Derek were roommates and just decided to keep living together their second year because they enjoyed each other's company so much, and Isaac shared most of Derek's classes and they became fast friends. It hadn't ever been an issue that Derek was an alpha and they were betas, that he was a werewolf and they were human. It was an easy friendship, no politics, just equals.

Derek wondered if their bond could survive a shift in their dynamic. "I don't want to talk about it."

To his surprise, they respected his request.

Boyd grabbed a book from an open box and started filling Derek's shelf, just like he had last year. Isaac offered to go grab them all lunch from Bruin Cafe with his swipes. Easy.

An hour later, Derek was unpacked, and Boyd and Isaac, comfortable with him as ever, were sprawled on his meager furniture, eating and talking, when someone knocked rapidly on the door.

"Come in," Derek said, standing up and tossing the empty food containers in the trash.

"RA—Derek Hale—RA Derek?" The kid, obviously a freshman, looked wide-eyed around the room at the three upperclassmen, still wearing the "Hi, My Name Is—" tag from welcome week. "Which of you is the RA?" he asked, his gaze already settled on Derek.

Something strange and new inside Derek preened at being recognized as the clear authority of the group.

Derek eyed the frantic boy in mild alarm. He was pale, blond and tremendously freckled, wearing crooked glasses and stinking of anxiety. "What."

Isaac snorted behind him and Derek shot him a glare. It wasn't like being an RA suddenly gave him perfect manners.

"Ants! I need something to deal with ants. Immediately. Do you have anything? Didn't they give you a supply to handle these things?"

Derek sighed, rubbing his eyes. He'd forgotten how stressed the last RA looked on frosh week.

"How about a little more information before I start handing out poison, alright?"

"Albert Douglas, room 314."

"Right. So, you are saying there are ants in 314?"

"Well." Albert looked at his shoes. "I'm pretty sure."

"I see." Derek ignored the snickering from behind him and tried to think of a reasonable question to ask. "Where are you seeing the ants, then?"

"Er, I haven't yet."

"You haven't seen ants. Then what are you worried about?"

"There _might be_ , and someday soon. My roommate is eating Doritos by the handful, and there are crumbs everywhere. _Everywhere._ Ground into the carpet. That is exactly how you get ants. I Googled it. We'll have an infestation within a week! And then what are you going to do?"

"I think I'll deal with it then, Albert. In the meantime, why don't you try asking your roommate to stop getting Doritos on the floor?"

"You don't understand. I can't even pronounce his name." Albert motioned with his hands like he was measuring the size of the name, maybe the complexity. "How am I supposed to start talking to him?"

Derek looked to Boyd, who just shrugged. Isaac had his face turned, badly hiding his laughter. _I_ _am so not ready for this_ , Derek thought for the hundredth time that day. He looked at Albert and remembered how Laura said she just 'read' people. He took in everything: Albert's hopeful expression as he looked up at Derek, his bitten-to-the-quick nails, the sharp scent of hand sanitizer.

"Look, Albert," he said, making an effort to be gentle. "There are going to be challenges this year. Roommate challenges. Everyone goes through them. Being away from home the first time, everyone is nervous and expressing themselves differently. Some might be eating their way through their stress. Some might be working on setting their room exactly right."

Albert quirked a smile at that, and Derek knew he'd found the best approach. He laid a hand on Albert's shoulder. "Open communication is the key."

"Open communication." Albert blinked, clearly expecting a solution more in line with getting a new roommate.

Derek nodded. "You're a smart guy—you got into this college, right? You'll get through this by talking it out with your roommate." When the scent of Albert's anxiety spiked, Derek quickly added, "I also have this vacuum that you can check out from me."

Albert's face brightened. "Oh! That's great! Can I use it anytime?"

"There's a schedule posted on the Hedrick Hall website, but if you catch me in the room you're welcome to it, or just shoot me an email. Here." Derek pulled the vacuum out from the closet full of supplies and handed it to the freshman.

Albert disappeared after a thankful smile and a determined nod, hefting the vacuum back to his room.

"He's not going to last a week," Isaac said. "And now I'm in the mood for Doritos."

Boyd came up behind Derek and clapped his shoulder. "That was actually pretty impressive."

They stood in the hallway watching Albert inspect the little Red Dirt Devil with a small smile on his face like he'd been thrown a life preserver.

It felt, well, _mildly_ impressive. It felt good. Derek stretched, letting a bit of tension out of his shoulders. Maybe he could figure this out.

 

* * *

 

Derek was on his way back to his room with Boyd and Isaac when someone stopped him in the hallway. "You dropped something."

Derek took the paper from the outstretched hand of the other student. Her long blonde curls bounced as she cocked her head and smirked. "I don't think I—" he started to say, but then she'd already turned and walked away with her hips swaying.

He looked down at the paper that he was sure wasn't his. It was a torn out sheet from a spiral notebook with a name and number on it. "For fuck's sakes."

" _When you meet that special someone, their scent will knock you on your ass,_ " Laura had once told him. Derek crumpled the paper in his hand; it certainly wasn't happening for him.

It wasn't like he believed that pheromones could lead you to your soulmate anyways. Sure, he accepted that there was a certain level of compatibility that your body acknowledged through scent, but it wasn't like it guaranteed a happily ever after. It was just… chemistry.

And Derek had never experienced it, that was all.

"Third one this week. Why does this keep happening?" Derek muttered to himself.

"Yeah, that's really strange," Boyd said, but his tone was deadpan and his look suspiciously blank.

"Well, don't look at me. I have no idea how the entire student body has just realized you're smokin' hot or something," Isaac added, more sincerely. "I passed Albert's Dorito-eating roommate in the hall yesterday, and as he watched you walk away, he muttered, 'damn, that ass'. Weird shit going on. You have the same ass as you did last year."

Derek sighed, pushing open his unlocked door and heading into the peaceful scent of his room. It was relaxing, being away from the chaos of all the scents of the different people on campus. It had never bothered him; scents had always been a quiet hum at the back of his mind. Now, it took constant effort to stay focused.

Boyd stretched out on the couch, and Isaac opened Derek's mini fridge, grabbing himself a soda. He shut the fridge a bit too hard and the shelf next to it shook, toppling some of Derek's books as well as a locked file case onto the floor.

Isaac put the books back, holding the case with interest. "What's this?"

Derek grabbed it and put it back on the shelf. "Confidential heat partner requests." When Isaac reached for it again, mischievous grin on his face, Derek slapped his hand. "Don't. And I'm serious, Isaac. It's my responsibility to keep my copies of those forms _confidential._ I only have them in case of emergency."

"Heat related emergency?" Isaac asked with glee. "Like if some omega gets into it, you 'handle' the emergency?"

Boyd rolled his eyes. "He asks the person listed, Isaac. It's part of the student health policy. Omegas keep the names and contact numbers of people they approve for heat assistance as an alternative to going to the heatroom in the health center."

Isaac narrowed his eyes. "Why do you know so much about this?"

"Because I'm Erica's." Boyd shrugged. "She went into heat during final exams last year. A nurse found me, explained the situation, and asked if I wanted to help. Of course I did. In the end we got to retake our exams, had more time to study, and shared an awesome couple days together. We were only dating for about a month, so I was surprised she'd put me down."

Isaac looked confused. "So you didn't know?"

"Omegas can list up to five people. Whomever they trust enough," Derek said. "As long as they live in a five mile radius and are of age. Of course, it doesn't guarantee that the person will agree to help them during the heat, but it's a good option to have, knowing there are people with pre-approved consent that the school can reach out to."

"Ah," Isaac said, poised to ask another question.

"No more heat talk," Derek said. His imagination was already conjuring up pictures of a pink mouth, wanton and gasping, panting in heat. It was just the cherry on top of the sundae of all these ridiculous alpha urges.

The first two weeks back had been a blur of school work, RA responsibilities ("No, Jackson you can't park here even if you had a professional sign made."), getting hit on constantly, and to top it all off, figuring out his newly awakened alpha instincts.

Whatever was happening to him, it felt every bit like puberty—emotional, out of control and impossible to stop.

 

* * *

 

"This should be a twenty-four hour library," Derek muttered to himself as he joined the other students getting ushered out of Powell as eleven o'clock chimed from the clock tower.

"I would move in," the guy beside him said. His eyes were bloodshot and he hadn't shaved in days. It was probably good he got kicked out of the library. "And even then, I'd never pass. Fuck. I'll hate this."

"Richard, right?" Derek asked, recognizing his face. He was the sophomore with an architecture major. Room 317, if Derek recalled correctly, and he was looking pretty rough. "You doing okay?"

"No, I'm really not," Richard said, his laugh a touch hysterical.

Before Derek could ask if he wanted to talk about it, Richard stuffed his earbuds in and stormed off. Derek made a mental note to check in on him later.

He guessed he could pop by the computer lab; it was open until two, but every available seat was usually taken with students working hard (or hardly working).

The dorm had been rowdy tonight, and Derek had snuck off to try and get some studying done in a little peace. Now it was back to his room with still two chapters to review, and the chance of things having quieted down during prime party hours on a Thursday night was just short of impossible.

Maybe by eleven the underage freshmen would have been buzzed enough from their illegal stash to head to an _actual_ party on frat row instead of causing chaos in the dorms. It was his only hope. Derek didn't think he could survive breaking up another 'the floor is lava' game or mattress jousting in the hallway.

Derek made his way through the halls, listening carefully for trouble. The halls were empty and most doors were closed, but piercingly loud music echoed from 307, 310, and 323. Derek could hear laughter and boisterous conversation echoing from the room, and it definitely sounded like more than four people in one dorm.

A party.

He sighed. He had a good talk with the freshmen on his floor about underage drinking and his responsibilities, but he also knew if he was an absolute hardass and tried to bust everyone, they'd just go and party on another floor. Or maybe drink themselves sick. Derek had felt like he made a good impression about keeping the noise down and _absolutely no parties,_ and Boyd had said that his smart drinking habits presentation was going to save someone's life.

So far Derek had gone without having to call for anyone to get their stomach pumped, unlike the RA on the fifth floor, so he thought he'd done well so far. Hopefully tonight remained a quiet one.

The whiteboard on Derek's door was still the same; Derek smiled at the squiggly happy face doodle Erica left for him yesterday, and there was a note from Boyd about coming to his Ultimate Frisbee game this weekend. He pushed open the door without a second thought.

It must have been the pounding bass across the hall that made him completely miss the heartbeat on the other side of his door. Derek usually left his room unlocked; he had an open door policy for people to visit if they needed to escape their roommate for a few minutes, or needed any supplies from the massive stash of condoms and lube that Student Health had provided him with at the beginning of the year.

But he'd never once come home to find his room occupied.

And never like this.

A freshman in nothing but a towel slung low on his hips was sitting on Derek's bed, reading one of his textbooks nonchalantly. Seconds ticked by with Derek standing there, stunned in place, senses completely aflame.

_Omega._

The scent hit Derek hard enough to nearly knock him backwards.

This wasn't just a casual walk by and vaguely noticing that they smelled kind of nice. This was a scent that filled the room, filled his _head._ It consumed the space, like the omega had been here for a while, touching his books, his desk, his _bed_...

Derek was completely unprepared, too, for the way his scent mixed with the omega's own, that the joint scents smelled right to him, _mine mine mine,_ that called to him to take a step closer, to rub his hands…

Derek squeezed his eyes shut, shaking off the fog.

It wasn't the first time this year someone had basically thrown themselves at Derek. He'd gotten pretty good at point blank saying he wasn't interested and glaring until they gave up. But then again, no one had ever been so _tempting._ He closed his eyes and grit his teeth, focused on the fresh air from the breeze coming through the open window, the dumb joke being told three doors down, the laughter from the window below him.

When he opened his eyes again, it was with a clearer head. He tried to think logically. The guy's hair was damp, and the scent of sex—that had to be from jerking off in the shower right before heading to Derek's room—and pheromones still clung to him. That was all that was happening here. But for Derek's sanity, this cute freshman needed to get his mole-spattered chest the fuck elsewhere.

"Get out," Derek said, slamming his textbooks down on his desk. He didn't care what this guy was looking for, but it was not happening. He sat in his desk chair, swiveling so his back was to the intruder, and opened to the next chapter.

"Rude."

"I said get out."

"What the hell, man! You're the RA!"

"Yes, and whatever you are looking for tonight, it's not happening."

"What? I—" The kid looked down at himself, as if realizing for the first time that he was basically naked. "Oh my God. Did you think I came here to ... what, seduce you?"

Derek's back stiffened and his fist clenched to suppress the rumble building in his chest.

"You did! You asshole! Because I'm an omega, I'm clearly just horny and waiting to be mounted?"

"I didn't say any of that. I just don't want what you're offering."

"Well, _I_ am not on offer, buddy," the guy huffed. "Why would you even think..."

Derek turned and gave him an incredulous look, gesturing to his state of undress. "Really?"

"Oh, well, fine. I _am_ a bit naked, but I got locked out while I was in the shower. Stupid roommate," he said. "Our room is right beside the showers. I told him I'd be back in a sec. But no, he left for the weekend, lucky asshole doesn't even have class on Fridays, and totally locked the door behind him while I was in the shower. I can deal with the vacuuming, but he's ridiculous about locking the door, man. Even if he's in there alone, the door is locked. I'm gone for two minutes to get a snack from B-caf... door's locked. Now this." He flopped backward onto the bed, as though he'd forgotten while ranting that he was clad in nothing but a towel.

His legs spread just enough to flash a tantalizing glimpse of pale thigh.

Derek's cheeks burned.

"He's killing me," the omega said, still in the throes of his frustrated diatribe.

This was killing _Derek._ He couldn't move. He'd gotten a fucking hard-on because he saw some thigh. It was mortifying.

"Get off my bed," Derek growled.

"Sure, man. Whatever." The guy stood, adjusting his towel haphazardly. "I just need you to let me back in my room, then I'll be out of your hair, grumpy."

Derek shot out of his chair, grabbing the envelope of keys from his desk drawer and darted from the room, not checking if the omega would follow. He needed air that wasn't making his head spin.

"Room number?" he asked as he heard the freshman jogging to catch up. He shot a look back, saw him scrambling to keep his towel in place, and caught a peek of sharp hipbones and a thatch of dark hair that Derek wouldn't be forgetting any time soon.

"314."

"Right." _Of course, the unpronounceable roommate._ "Dorito man."

"I dropped one chip, and Albert vacuums the shit out of our place. I can't live like this."

"I'm not your mother," Derek said, trying to talk without breathing, without _looking_. "I don't care."

Derek shuffled through the envelope, struggling to find the correct keycard. The omega stood close behind, shivering from being in the cool hallway in just a towel and wet hair. It took everything for Derek not to pull him close and warm him with the body heat of an alpha.

He bit back a groan as an unbidden image came to mind: crowding the omega up against the wall, yanking the towel off his hips and then capturing his lips in a hot, furious kiss—

"Don't forget your key again," Derek said, shoving open the door to 314 at last.

The room's air was stale, but beneath the junk food and unwashed socks, the sweet scent of this particular omega clung to everything, as it likely would in Derek's room for the next few hours.

The omega pushed past him to get through the door, and a bare shoulder brushed his. Derek flinched away at the heat of the contact; his control was barely holding on by a fine thread. "If I ever catch you waiting in my room again," he said gruffly, "I'll report you to Student Housing."

He turned and briskly walked away.

A sarcastic voice followed him down the hall. "Nice to meet you too, asshole!"

Derek's claws dug into his hands until his palms dripped with blood. It did nothing to soften his erection, or dissipate the delicious scent of that annoying omega from his nose.

 

* * *

 

"If you drop one more curly fry on that carpet, I swear to God, Stiles, I'll..."

Derek slowed his walk down the hallway, his curiosity getting the better of him. Noise from 314 was pretty common, but usually it was the hum of the vacuum. Albert had never raised his voice before, so Derek was kind of curious to hear what was going on.

"I'll..." Albert huffed from behind the closed door. "I'll make you eat it after it was on the floor."

"Oh, yeah? What if I _want_ to eat it?"

"What are you—" Albert asked, his heart rate accelerating. "No. Put that down. Oh God, Stiles, don't eat—"

With a shout of horror, Albert threw open the door, nearly knocking Derek over in his escape. He looked back, shouting into the room, "You are the most disgusting creature I have ever met."

Derek peeked through the open door to see Albert's roommate, _Stiles_ , happily chewing. Stiles caught Derek's eye and raised his eyebrows, smirking back at him and grinning cheekily around the disgusting mouthful.

"Five second rule," he said with a laugh, and he kicked the door shut in Derek's face.

 

* * *

 

Derek decided it was in his best interest to avoid Stiles; his unexpected attraction could only be a reaction to pheromones. Even after the disgusting chewing-with-the-mouth-open moment, he inexplicably found Stiles captivating. It _had_ to be a physiological alpha/omega response.

Unfortunately, the universe hated Derek. He had no idea how he'd gone the first two weeks of school without seeing a guy who lived on his own floor. But now that he was making conscious effort to avoid him, Stiles was everywhere.

Walking past 314 everyday to get to his room, he couldn't help but notice, to his frustration, how often they left their door wide open.

Today, he forgot how to use his legs as he peeked in to see Stiles vacuuming—and _dancing_ —his pert little ass shaking it off with Taylor Swift. Albert was in the background, clapping delightedly, then as Stiles shut the vacuum off, Albert threw his arms around Stiles for a hug.

Rage flared hot in his chest, and in an instant, Derek had dropped his books and burst through the door.

Taking in Stiles' wide-eyed reaction, Derek paused. What was he doing?

"Derek!" Albert said brightly. "Thank you so much for all the advice on communication. We figured out the best way to—"

"I gotta... go," Derek said, grabbed his books and darted for the door. From the corner of his eye, he caught the curious look Stiles gave him. Mortified, he fled.

Derek tossed his books in his desk and flopped onto his bed, breathless. After a moment's indecision, he pulled out his phone.

Laura was an Alpha, maybe she'd understand.

To his surprise, she listened without comment. Derek told her everything, from finding Stiles practically naked on his bed to almost attacking Albert that afternoon.

"It's simple. You were jealous," Laura said.

"Jealous—of _Albert?_ " Derek scoffed. "No way. It's not like Stiles and I are—I barely know him! He can hug anyone he wants to."

"The logical side of you knows that, but you're an alpha, too."

"Not _that kind_ of alpha."

"You're still an alpha, Derek. And a werewolf too, don't forget. Our instincts heighten _everything._ And from the way you described it to me, it sounds like this omega's scent really caught you off guard when you first met."

"Because he was _naked_ —"

"Okay, but you live on a floor with shared bathrooms, and this is your third year showering alongside other naked omegas and alphas and no one's scent has ever done anything like this to you before."

"I just like his scent. That doesn't mean—" The whole idea was ridiculous. If Laura started talking about mates, he was going to hang up.

"I know you don't like the _m-word,_ but it's about compatibility, Derek. I know it sounds very caveman, but the fact of the matter is you saw someone touch Stiles and your instinct was to defend your claim."

"Claim? Seriously?" Derek rolled his eyes. He should have known Laura would be overly dramatic about this.

"It's instinct, years of evolution making alphas weird like that. There are entire university courses studying it."

Derek groaned. "I'm sure you took every one of them. So how do I make it stop?"

"You should ask him out."

"Laura."  
"Fine, at least try to get to know him," Laura said. "Your body is responding to his scent—just spend more time together and you'll learn to control it. When I first met Michelle, I was a complete mess whenever she was around, and when we started dating it got easier."

"So you're saying I need to build up my tolerance," Derek said. That was actually a really good idea. He just needed to re-learn how to get his instincts under control. Like a fifteen year old, he thought bitterly.

"Tolerance? Derek, are you even listen—"

"Thanks, Laura. Gotta study, bye!"

 

* * *

 

A few days later Derek still hadn't figured out how to hang out with Stiles to build up his so-called tolerance. He couldn't study with him because they didn't have any classes together, and he didn't know what Stiles liked (other than Doritos) because they hadn't even had a conversation yet.

Derek was crossing off another bad idea from his list, completely frustrated, when his partially open door swung wide. Stiles' scent filled the room, and in an instant, Derek was hard. He flipped his notepad over and held it in front of his lap, thinking furiously about the complicated equations in yesterday's homework, his cheeks hot at his dick's ridiculous reaction.

"Hey, Derek," Stiles said without any of his usual sarcasm. In fact, there was a friendly smile on his face.

This didn't bode well for Derek. Or his dick.

"What are you up to this fine Wednesday afternoon? Done with class?" Stiles' smile stretched from ear to ear. It was unnerving.

"Yeah, early day for me," Derek said. "Is everything okay?" He took short, shallow breaths, hoping that less of the scent would make his dick behave.

Stiles lingered in the doorway and gave Derek a hopeful look. "Sure, everything's great, I also am done for the day. And hey… do you know Scott McCall? Freshman, like me, lives over in Rieber, pre-med, my best friend."

Derek nodded. He'd seen Scott a few times since his help with the couch and Scott had even joined the Ultimate Frisbee team at Derek's suggestion. After their bumpy first meeting, he'd really warmed to Scott. Scott was a nice guy, good team player. The kind of guy that made being an alpha look easy. He'd probably make a team captain one day.

Stiles slumped against the doorframe, rubbing against it. Damn. Derek was going to have to wash that later, otherwise he was going to get hard opening and closing his own door.

"Well, he's getting off work down in Santa Monica soon, and he forgot his ID at school, and he's out of change for the bus, and I heard you had a car? I mean, I would bus it over to him and back, but that's like an hour…"

"You want me to pick him up? I—" Derek looked down at his hopeless list of ways to get used to Stiles' scent. It was going nowhere today. "Sure, no problem. Where is he?"

"Awesome! It's the Liechester Animal Clinic. I think it's on 4th? Or maybe 5th. I don't remember." Stiles' grin broadened. "Maybe I could just show you?"

"Alright," Derek said, voice cracking over the word. He threw his notebook with the useless list on the desk, grateful for this opportunity to build up his tolerance. Maybe the universe didn't hate him. He grabbed his keys and tried to hide the smile that had spread over his face.

Stiles made small talk with other students on the elevator ride, but seemed to grow nervous as he followed Derek on the walk through the parking lot.

"You know, I wasn't expecting you to agree," Stiles said. "It's kinda weird. I thought you hated me."

"I don't hate you."

"I mean, the glaring, the 'get out of my room,' all that sounded like you hated me." Stiles gave him a searching look, like he was trying to figure something out.

"I was having a bad day, okay? I didn't mean to be an asshole."

"Huh," Stiles said, letting the conversation drop and appearing to get lost in thought.

Stiles whistled when they reached the Camaro. "Nice."

Derek felt a small surge of pride rush through him, and then to his horror saw in his window's reflection he was actually puffing his chest up, like some stereotypical peacocking behavior that he swore he'd never find himself doing. He caught himself and beeped the doors unlocked. Stiles settled into his seat like a cat finding a perfect spot to take a nap, squirming and wriggling against the leather.

Derek gritted his teeth, his hands white-knuckled on the wheel. "Comfortable?"

In an enclosed space, Stiles' pheromones absolutely _saturated_ the air.

Derek's life was hell.

Luckily, Stiles seemed to find words easily. The conversation covered the usual gamut: favorite restaurants, people changing majors, hometowns. Soon enough Derek forgot about Stiles' scent and focused on Stiles' really odd theories about Star Wars.

"Look it up. It's a huge plot-twist that never happened. Jar Jar was supposed to be the villain mastermind! He was like, the Sith's version of Yoda!" Stiles exclaimed.

"No possible way. Jar Jar was annoying and a huge waste of—"

"No, no, listen! The audience's negative reaction to Jar Jar was so extreme, Lucas had to tone him down and take out the reveal. But the bones of the original plot twist are still all there! Oh, hey, turn right here!"

Derek blinked; they couldn't possibly have gotten there already. Following Stiles' directions, he pulled over so Stiles could pop onto the sidewalk and wave excitedly at the window of building. Soon enough Scott bounded out and wrapped Stiles in a hug. Derek bristled.

"Thanks so much for getting me, dude. I'm always taking my ID out when I go to the gym and then forgetting to put it back in my wallet," Scott said, beaming at Derek.

"No problem."

"It's so weird that you guys know each other," Stiles said.

"Yeah, Derek plays Ultimate with me. He's one of the best on the team." Scott smiled and hopped into the backseat. To Derek's shock, Stiles followed him in, ignoring the front passenger seat.

Derek chauffeured them back to campus, feeling like an idiot, as Scott and Stiles chatted in the back. The third time they finished each other's sentences, Derek nearly swerved into the other lane. Having Scott, another alpha, press his shoulder to Stiles' as they roared in laughter over a shared memory was excruciating.

He reminded himself that Scott was in a relationship with Kira, another Ultimate Frisbee player. He'd seen them together often enough, and it was common knowledge they were mates.

And Derek liked Scott. A lot. He was mature for a freshman, had a good head on his shoulders, and _he wasn't dating Stiles._

Besides, it didn't matter. Derek didn't care. He was just… He was just getting more exposure to build up tolerance to whatever Stiles' scent was doing to him. Stiles could date whomever he wanted.

It really _shouldn't_ matter.

He pulled up at the circle at Rieber to drop off Scott. Maybe he'd have another moment with Stiles on the walk back to their room. But then both of them got out of the car.

"Thanks, Derek!" Scott said, tapping the car roof and waving.

Lost in his feeling of annoyance, he almost missed Stiles lingering outside his window.

Stiles leaned in and Derek looked up. His shirt's neckline slipped, revealing a tantalizing hint of collarbone. "Hey, I really appreciate this," Stiles said.

Oh God, Derek wanted to kiss him.

He tried to say "yeah" and "no problem" at the same time, and it came out, "Your problem."

Horrified, Derek just nodded and drove off.

 

* * *

 

Three days later, Derek was procrastinating on a paper when Stiles burst into his room waving a bag of unpopped popcorn.

"Hey, Derek! My favorite RA!"

"I am your only RA," Derek said. "Unless you're cheating on me with another floor."

"I would never!" Stiles declared. He held out the bag as a question.

"Yes, you can use my microwave," Derek said, waving at the appliance. He checked the door that Isaac wasn't hovering around to announce that Derek never let anyone use his microwave for popcorn—he hated that his room smelled like a movie theater for hours when they did. Today, he hoped the chemical butter smell would help mute his reaction to Stiles.

After a few beeps, the microwave hummed to life, and Stiles turned back to him. "Okay, so there's a Mets game tonight and everyone's watching a Project Runway marathon in the common room. "

"Sacrilege," Derek said, knowing where this was going by the way Stiles was eyeing his TV.

Stiles steepled his palms. "Help a baseball fan down on his luck?"

Derek snorted. He'd been resisting watching until after he finished his paper, hoping to catch the last few innings as a reward, but he wasn't being productive at all.

"Have a seat," Derek said. He flicked on the TV, and Stiles twirled around to the beeping of the microwave, pulling out the bloated bag.

Stiles stretched out over the couch, eating popcorn from the bag that was slightly burnt in one corner. With each mouthful, three pieces of popcorn dropped to the floor. "Sorry," Stiles mumbled around his full mouth when he caught Derek staring.

"It's fine," he said, and in a moment's boldness, added a wink. "I know where the vacuum is."

Stiles choked, and Derek watched helplessly as Stiles turned red, coughing frantically to dislodge the popcorn he'd swallowed wrong.

Clearing his throat, Stiles motioned towards the fridge, his neck all blotchy pink. Derek quickly pulled out a can of Mountain Dew and tossed it over.

"Thanks," Stiles gasped when the can was half-emptied and he could breathe again.

Derek shrugged, joining Stiles on the couch so he could be close if the Heimlich became necessary. Besides, he was getting no work done anyway.

"Thor's hot tonight," Derek said, digging his hand in the bag of popcorn.

"You—" Stiles looked like he was ready to choke again. "You like the Mets?"

Derek tossed a piece of popcorn into his mouth and caught it. "My sisters like the Yankees. Of course I like the Mets."

Stiles blinked at him a moment, his cheeks still red from coughing, then he looked back at the game. Noah Syndergaard, aka Thor, just got three up, three down in the top of the fifth. "Hells yeah. Bringin' down the hammer."

Derek laughed, absorbing Stiles' excitement until he was cursing the umps, screaming at the video replay and denying absolutely that the guy sliding home was out.

It was a good afternoon; after they finished the popcorn, Stiles ordered pizza, the Mountain Dew stash in his fridge got deeply depleted, and the Mets kept the lead the entire game.

Everything was comfortable, the conversation and the company were excellent, and despite the overpowering smell of popcorn, Derek _wanted_ Stiles even more.

_Fuck._

It wasn't just a physical reaction, the biology of an alpha triggered by an omega's scent.

Derek _liked_ Stiles. Like, a lot.

Once the game finished, the Mets slamming the Royals 4-2, Stiles stood and stretched, revealing a pale expanse of skin and a trail of dark hair leading from his navel, down, down...

Derek forced his gaze to the window.

"So… there's a doubleheader on Friday against Detroit," Stiles said, a hopeful lilt to his voice.

Derek was so fucked.

 

* * *

 

Several things happened over the course of the following weeks: Derek's TV got a work out, his couch formed a low-spot where Stiles' butt took up residence, his floor needed to be vacuumed twice as often, and his assignment grades dipped slightly lower than usual.

One thing that markedly did _not_ happen: Derek did not develop a tolerance of any sort for Stiles' scent, nor did familiarity lessen the agony of his constant presence in Derek's room.

It was a constant ache.

Laura's advice to "get to know him" might have had an ulterior motive, now that he thought of it. Derek realized spending more time together wasn't doing anything to alleviate the constant barrage of fantasies about his new friend. In fact, it seemed to make it worse, because the more Derek got to know him, the more he liked him as a person.

It made Derek's life a constant exercise in self control. At some point, he realized that the fantasies weren't just sexual; he'd daydreamed in class the other day about holding Stiles' hand while they were watching the game, and seeing him smile.

In that moment, Derek knew he was in over his head.

 

* * *

 

Derek's hips jerked restlessly. He twisted and turned in his sheets, trying to find the friction he needed. The tingle started low in his belly and he knew instinctively what was about to happen. He dreamed of a tight grip around his cock, squeezing until he was breathless, until his blood burned in his veins. He gasped, lungs filling with the sweet scent of omega.

_Bang. Bang. Bang._

Derek's eyes flew open. He blinked at the darkness, dragging in a ragged breath. His sheets were damp beneath his back. His cock was hard and aching, trapped in his boxer briefs. He reached down to give it a squeeze and hissed as the pressure sent a wave of pleasure through him.

Gingerly trailing his finger down the shaft, he felt the flared bulge at the base. He'd actually popped a knot from a _dream_. He wet his lips, imagining the taste of salty skin still there. He could almost swear it was real. The ghost memory of that dream omega haunted him, the eyes that challenged Derek to hold him tighter, the smirk Derek had kissed until his lips were plump and swollen.

He fisted his cock tighter.

So close.

_Bang. Bang. Bang._

He groaned, realizing the banging that had woke him was coming from his door. Scrubbing at his face to shake off his sleep, he stood. Gravity didn't help the bulge in his underwear and there was nothing on earth that would help shake it off in the ten steps it took to get to the door.

Swallowing his embarrassment, he waddled over and cracked the door an inch. "What?" he said, the word firing from his mouth like a weapon.

"About time!"

Squinting at the brightly lit hallway, Derek banged his head against the doorframe as he recognized Stiles. "There's no game on at midnight, Stiles."

Stiles' eyes narrowed, and with his hair wet and plastered to his forehead, he looked far less adorable and far more menacing. It was, unexpectedly, a good look for him.

"My fucking faucet," he said by way of explanation. Drenched and fuming, Stiles waved said faucet—it was raised as if he'd been using it to smash against Derek's door in lieu of knocking.

Derek looked between Stiles and the faucet, which was identical to all the standard sink faucets in every dorm room and clearly not attached to the sink at the moment. "How?"

Stiles' t-shirt clung to his goosebump-covered skin and his sodden jeans hung low and heavy on his hips. "Rust. Decay." He waved the corroded bottom in Derek's face. "Whatever… I don't know. The piece of shit just came off in my fucking hand. And the sink— _pow_ —exploded."

Derek pulled the door open wider, shivering at the chill of the hallway air as he stood in only his underwear. Fuck, Stiles smelled amazing today. Just as intense as that first day in the towel. There was no way Derek's erection was going to go away soon.

Unfortunately, there was a major plumbing problem and it was Derek’s responsibly to deal with it.

Stiles' eyes flicked over Derek's body; the lights were off and Derek hadn't quite stepped into the hallway yet. He hoped he was at least a little hidden in the shadows.

"That's not fucking fair," Stiles muttered, then ran his hands through his wet hair until it was sticking up in every direction. "Look, I wouldn't normally... ugh, disturb the beauty sleep required for a body like that, but it's Niagara Falls in my room right now."

"Right," Derek said, resigned. He swung the door open for Stiles to step in while he scrambled for pants. He grabbed a pair of jeans from the floor, hopping up and down to get them on as quickly as possible.

"Thank God Albert's not here or he'd be ranting about mold—" There was a sort of whine behind him, and he turned to see Stiles staring at Derek's bed, his nostrils flaring. "Jesus, were you—"

"Sleeping," Derek snapped, but it came out like a rumble. He blamed it on trying to get his zipper up. He stalked out of the room, still buttoning his jeans.

314 was a mess, the carpet was a swamp, and Albert would have every right to be worried about mold. Niagara Falls was still roaring from the wall as water sprayed in an arc from the hole where the faucet had once been attached, and Derek immediately dove under the sink to turn off the water valve.

Kneeling on a cold, wet carpet was a painfully quick way to shrink a boner.

Derek stood, dripping wet and grateful he hadn't bothered with a shirt.

Stiles' cheeks pinked, and Derek was suddenly very aware of the sweet scent flooding the room. He wasn't sure if he just hadn't noticed before or if something had triggered its release, but his wet and cold dick was stirring back to life as his dream came rushing back to the forefront of his mind, except now very clearly starring Stiles.

Fuck. Derek wanted so badly to make it a reality. Even right here on the soon-to-be molding carpet.

He needed to get himself under control. "You know, I'm going to have to call maintenance," he said, hoping he sounded casual. "You can wait in my room until this is cleaned up. It'll be a bit. Just make yourself at home."

Stiles looked around the room like he wanted to argue that he should stay, but literally everything was soaked. The spray had even reached Stiles' bed. At last, Stiles snapped his jaw shut and nodded. "Thanks," he muttered and slunked out the door.

The moment Stiles left, taking his scent with him, Derek itched to go after him, to _take care of him_. He should have offered Stiles a towel. Maybe warm, dry clothes. Maybe food. Maybe _his bed._ He sighed and the carpet beneath his bare feet squished uncomfortably.

He had other things to focus on.

He pulled out the phone, still in his pants' pocket from the night before, and did his job.

 

* * *

 

Two hours later, Derek was finally done. The wet/dry vacuum from Facilities storage had done most of the work. In the morning, he would need to get Maintenance up to check the damage, but for now three dehumidifiers were humming away, and Derek was wet, cold and exhausted.

He stood under the shower, trying to get some warmth back into his body. His teeth chattered despite the steam. He might need to skip his eight o'clock class; he'd been feeling achy and uncomfortable since he'd been woken. Maybe he was coming down with something.

Derek passed by a hallway window, and he could see the faint edges of the sky just beginning to lighten. Great, the sun was almost up.

Noticing his door was ajar, he stepped in tentatively.

His lamp was on, which he knew hadn't been when he'd left, and it set the empty room full of long shadows. Stiles' scent was everywhere. As Derek stepped forward to search for the source, the floor crinkled beneath his feet. His gaze dropped to a crumpled, empty bag of Cool Ranch Doritos beneath his foot. He grinned to himself, his chest warming at the sight more than the shower managed.

He stepped deeper into the room, and just as he heard the familiar heartbeat, the lump of blankets on his bed made a soft snore. The sight tightened his chest and he closed the distance between them without questioning whether he should. The responsible thing might be to leave, but it was no more than a fleeting thought.

His lungs filled with the warm, sweet scent of Stiles, overwhelming his senses. It wasn't just _Stiles_. The scent was Stiles wearing Derek's shirt, sleeping in his bed, lying on his pillow. It was the scent of Derek and Stiles combined. And it was perfect.

A rush of heat came over him as Stiles turned towards him, blinking drowsily. It struck him then how badly he wanted this, _needed_ Stiles in his bed. His body ached for it.

Stiles' sleepy eyes blinked up at him and he smiled, slow and inviting, like he'd been waiting for Derek.

"You're sleeping in an alpha's bed," Derek whispered to the quiet room.

"I know," Stiles said, his voice dark and rich, a soft rumble just on the edge of waking. "You said make yourself at home, right?" He threw back the blanket.

Stiles was wearing one of Derek's shirts, a little too big on him, the collar draped forward. His eyes glittered as he patted the spot next to him. "Does the alpha want to come to bed?"

Emboldened by the flirty challenge in Stiles' raised eyebrow, Derek moved forward, heart pounding nervously despite the confident step. Stiles held his gaze, eyes bright, his lips slightly parted. Maybe this was where they'd been moving towards—the countless baseball games, the conversations while they picked what to watch next on Netflix. No matter how much Derek tried to deny his feelings, falling hard for Stiles had been inevitable.

Derek was too tired to think. All he knew was that Stiles wanted him to sleep next to him. He was there, in Derek's bed, and everything about this seemed _right._ Derek slipped under the covers. For a moment, Stiles' bare thigh grazed his and the heat was searing.

Derek turned to face Stiles, hoping he wasn't reading this wrong, and reached out to brush Stiles' cheek with his thumb.

Stiles inched forward to meet the touch. "Derek, I wanted to…" He stared at Derek and his whole body seemed to quiet, absorbed in the look.

"Yeah?" The distance between them felt unbearable. They were in the same bed, with Stiles' face just inches away from Derek's. Their combined body heat had them sweltering beneath the blankets, but Derek refused to move and shatter the moment.

Stiles shuddered, his eyes glassy, a sheen of sweat on his forehead, and he leaned forward. He reached for Derek's hand resting on his cheek, and curled his hand around it, his palm radiating heat.

His skin was scorching hot.

"I don't get why I like you so much," Stiles mumbled, his words tumbling together. "You were so mean to me. And then you were nice to me. And sometimes you pretend to be mean, but you're really nice. Derek, you're so…"

Stiles surged forward just as Derek put together all the oh-so-obvious clues. He pressed a palm to Stiles' _unnaturally_ hot chest. "Stiles, wait."

"I thought—you—I was going to kiss you, because I asked you to bed and you got in and you gave me that cute look and I—I—Derek, I need to—"

Derek swallowed, ignoring the sinking feeling in his stomach. He got out of bed, feeling guilty at the stricken look on Stiles' face as he stepped back. "Stiles, I think you're in heat."

"No, I'm not due for another month," Stiles whined. "I can't be in heat. I _like_ you. I was finally putting a move on you and you're being all noble and shit… Just reject me like a normal person, okay. Don't blame this on my omega weirdness."

Derek tried to process. "You don't know what you're saying, okay? It's the pheromones. It's normal. You're reacting to me because you're in heat and I'm an alpha—"

"No, I _like_ you. I've liked you ever since that time you found me on your bed in nothing but a towel and threw me out."

"After your heat, we can talk about this," Derek said, digging his nails into his palms to focus on doing the right thing and not climbing back into his bed and kissing that frown off Stiles' face.

"I'm not in—" Stiles stopped, mouth open, finally thinking. He blinked and wiped the sweat from his forehead. "Shit."

"I'm going to get campus security to escort you to the student health center. You can get a heatroom or I can call your pre-approved heat partner to help you."

Stiles stared at him, wide-eyed for a moment, then threw his head back in a laugh. "You do that."

"I'm not sure what's funny, but I need to do what's right, Stiles. I like you, okay? And you are so—" he waved his hands at Stiles lying on his bed in a t-shirt and boxers, covers thrown back in invitation. "I _really_ like you. That's why I can't. Not like this."

Stiles sat up in bed. "You really like me! I hoped—"

"Stiles—"

"You keep my favorite Doritos stocked in your snack cupboard, which no else around here eats, and Mountain Dew in your fridge, even though you complain how much you hate Mountain Dew, and I know none of your friends drink that stuff." Stiles scooted forward, the blankets falling around him.

Fuck, those were Derek's boxers he was wearing.

"You—you're _hard._ Derek?"

Derek looked down, betrayed by his body—he couldn't help it. He was so used to just… being in some state of arousal around Stiles that he didn't notice it anymore.

"You're in heat," Derek said. "I know you are—and it doesn't matter how I feel about you, Stiles. Even if I wasn't your RA, I'm—I'm gonna do the right thing and get you where you can have a safe and healthy heat."

Stiles raised his eyebrows. "Fine. Call my pre-approved heat partner then."

Derek took a deep breath, regretting it once his lungs filled with the intense scent of omega in heat. His instincts screamed that it was _his_ omega calling out to be taken care of.

Stiffly, he headed to his shelf, taking out the padlocked case file. It took a moment for his shaking hands to get the combination right, but he found the file marked "M. Stilinski" and pulled it out. He opened the sealed envelope, scanned past the general medical information and found where Stiles had written the name of the one person he'd consented to share his heat with weeks ago.

He looked up in shock. "Me?"

Stiles shrugged, looking at the floor. "It wasn't like I thought you'd ever accept. That first week when you were giving all those speeches and tours, I couldn't get you out of my head. Your scent... well. I knew everyone was coming on to you, and probably half the second floor had you written down too, at least second or third on their lists. So why the hell not?"

Derek glanced down at the five spots available for omegas to name their pre-approved partners. "You only listed me."

"I didn't know anyone else unbonded I would trust like that. I still don't." Stiles looked up, catching and holding Derek's eyes. "Will you?"

Derek briefly imagined calling security, having them escort Stiles down to student health, and letting Stiles walk away from him desperate and alone. Being apart from Stiles was the last thing he wanted.

"Yes, of course I'll help you," Derek said. He dropped the file to the floor and stepped to the edge of the bed, waiting for Stiles to take the next step.

"Oh, fuck yes," Stiles said. He surged forward, pressing their lips together in a dry, rough sort of touch. He whimpered softly, gently ending the kiss with a hesitant swipe of his tongue.

Derek held him close, hardly daring to believe what was happening. His instincts quickly overpowered his brain, every nerve of his body alight with _yes, mate, mine, claim_.

"You taste as good as you smell," Stiles mumbled. "Like I thought you would. Like your bed smells. You taste a thousand times better than the way your bed smells. Kiss me again."

Derek laughed at Stiles' slurred words. "You aren't making sense."

" _You_ never make sense," Stiles said, poking Derek's chest with a finger, only to end up tracing over his pecs in lazy circles. Derek shivered as Stiles found his nipple. "It must be catching." His gaze flittered over Derek's face, hungry and desperate.

"You smell fantastic," Derek blurted. "You always smell fantastic." _You smell like mine._ He buried his nose in Stiles' neck, relishing the intensity of the scent there, how the heat of Stiles' body branded every place their skin touched.

He knew what it sounded like to be so obsessed about someone's scent. He wasn't crazy enough to deny what this felt like, what the effect Stiles had on him could mean. But right now he didn't care about biology or pheromones.

"You. Fuck. _You're_ fantastic," Stiles said, writhing in Derek's arms, like being still was impossible. "You know how I felt when I got here, and I opened your fridge and like… all my favorite stuff was in there? It felt so good, Derek, you take such good care of me…"

Derek's chest swelled at the praise. He peppered kisses over Stiles' lips, chaste to begin with but the tenderness gave way to frantic, desperate touches, like they couldn't get close enough. It was as though they needed to be inside each other's skin, and even then it wouldn't be close enough.

They couldn't stop touching, reaching, grasping at each other. Every inch of Stiles was so incredibly hot beneath Derek's hands.

Derek walked them back towards the bed, trying to lay Stiles gently down, but Stiles fell onto his back, pulling Derek forward eagerly.

"I'm regular as clockwork with my heats, you know," Stiles said. "Three times a year, no ifs, ands or buts, but then _you,_ Derek, this is for you."

He groaned, kissing Derek again, mouth hot and insistent, wrapping his legs around Derek's waist.

Stiles' words hung in the air. This was for _him_. His head spun at the thought.

"I need—Would you—" Stiles' voice cracked.

Derek leaned forward the few inches he need to capture Stiles' lips. "God, yes."

He shifted so he was covering Stiles head to toe, thrilling in the pleasure of his weight pressing down on Stiles' heat-wrecked body.

"I'll take care of you." He kissed Stiles' lips, his nose, down his neck, muttering, "I'll take care of everything." _Always._ He bit back the word before it escaped. He wasn't thinking straight. Stiles' scent was muddling his thoughts, as it had since the first day.

_When you meet that special someone, their scent will knock you on your ass._

"Fuck." Derek swore as the m-word popped in his head again. Derek shut his eyes for a moment, trying to think through the fog that clouded his brain. Stiles was here, beneath him, in heat and needing him. _Mate_ or not, Stiles' heat was now his responsibility, and he would do everything he could to make it perfect.

Leaning forward, he pressed their foreheads together and whispered, "Tell me what you need."

"You," Stiles said, "Just you. _Naked_."

With a soft laugh, he rolled off Stiles long enough to tug down the underwear he'd slipped on after his shower, then he helped strip Stiles of the T-shirt and the boxers he'd stolen from Derek.

"You can keep these," he said, trying to sound casual. The thought of Stiles sleeping every night in clothes soaked in Derek's scent settled nicely in his mind.

"Okay." Stiles grinned like he'd read Derek's mind and knew what it meant. Grabbing Derek's wrist, he pulled him close again, until Derek knelt between Stiles' bent knees.

"Like this?" Derek asked.

Stiles nodded, cheeks flushed.

"I dream about you," Derek said, his finger pressing tentatively at Stiles' entrance and finding it wet and open, heat easing the way. "You, like this."

Stiles' hips jutted restlessly, urging him on. "Please, I don't need—"

Derek tutted, letting his finger slip into the heat-slicked hole. Stiles arched his back, his hard cock bouncing with the move. Slow and careful, Derek added another finger, and after a few strokes, a third.

He kept his pace steady, slow and gentle as Stiles stretched around him.

"I dream about my cock deep inside you," he said, trembling with the exertion of staying in control. "And I wake up so hard."

"Please," Stiles rasped. "Another time you can—don't tease me now _."_

Derek reluctantly pulled away and opened his top drawer for a condom and lube. Instinctively, he reached for the unopened red box. Knotting condoms were expensive, and Derek only kept them around because it had been ingrained in his head that you never know when a partner would be in heat. He was grateful for that lecture at the moment and vowed never to mention it to his mother.

He fumbled with the condom, ensuring the specialized band was secured below the place his knot would form.

"Were you a boy scout?" Stiles asked, eyeing the box.

Derek shook his head. "Just the son of a doctor. Are you ready?"

Stiles grinned, grabbed a pillow and slipped it under his ass. "Hell yeah." He spread his legs, displaying himself. "I'm all yours."

Staring at Stiles' puffy, wet hole, Derek had to resist burying his head there and tongue fucking Stiles until he begged some more. But Stiles hadn't asked for that. So he tucked that thought away for later. He grabbed his cock, slicking the condom with lube, and positioned himself between Stiles' knees.

Derek let the tip of his cock just rest against the hole and waited for one last nod of approval. Instead, Stiles' legs wrapped around his waist and pulled him in. It was enough to breach him, the flared head of Derek's cock pushing past the tight muscle and slipping inside. Derek's arm shot out to steady himself as the sensation overtook him. Their bodies connected, finally, as they'd been drawn to for months.

Beneath him, Stiles gasped, dragging in air in long ragged breaths. "I knew you'd be amazing."

Derek bent to kiss him, brushing their tongues together between breaths as he slid in deeper. Stiles clenched around him, fisting Derek's hair as he swore with each inch of penetration until Derek was balls deep.

Dropping to his elbows, Derek sucked a mark into Stiles' neck, both distracting himself from coming too quickly and wanting Stiles to remember tomorrow morning what was happening the exact moment the hickey was given to him.

He tried to start slow, but Stiles squirmed under him, begging, "Come on, fuck, I need this."

Every bitten-off curse and moan from Stiles drove him faster, harder. His hips jack-rabbited until his muscles ached, until he was consumed by the need of pleasing Stiles.

Stiles glistened with sweat, cheeks a rosy pink and chest flushed with blood and heat. Derek knew he'd never again dream of a faceless omega when he had this to dream of. He needed nothing now that he had Stiles.

Their bodies moved together in a messy, noisy dance. Sloppy sounds of slapping skin and creaking bed springs filled the air, and Derek didn't give a fuck who could hear them.

The same tingle in his spine he'd felt in his dream began again. His knot was forming, starting to catch on Stiles' rim with each thrust. "I'm gonna—I can pull out."

"No." Stiles' fist gripped Derek's hair, pulled him in for another kiss. "Please, I want to come on your knot."

"God." Derek gnawed his cheek not to lose control at the words. "Just let me—we'll be more comfortable—"

He gave up trying to find words and just pulled out, shushing Stiles' complaint. He shifted them to be side by side, chest to back, and with a snap of his hips, he slipped back in. The angle change had them both gasping again. Only a few more jerks of his hips and Derek slammed in, locking himself in place and pressing bruises to Stiles' hips as he held him tight through the first pulses of his dick.

"Fuck, yeah." Stiles' hand flew to his cock, jerking himself through his own orgasm. His body shuddered, trembling in Derek's arms as his body tightened around Derek's knot.

Derek's teeth ached to bite the exposed neck, claim his mate for the world to see. But there'd be another time for that, time for conversations and time for proper discussion. Instead, he kissed Stiles' neck right at the spot the mating bite would be and whispered a promise to himself.

They lay in a tangled, sweaty heap, catching their breath in silence. Derek's cock pulsed again, spurting out a last bit of come, and his knot held firm. For a fleeting moment he regretted the condom, his instincts leading him on, a desire to fill his mate with his seed, to see him swell with their child—but that was idle fantasy, and a strange and new domestic one at that.

They were young and they had their whole lives ahead of them, and maybe, Derek hoped they could spend them together.

Stiles squirmed, locked still with Derek, like he was getting comfortable with being as intimate as you could possibly be. He let out a contented sigh and said, "My heat will be a couple days, you know. Like this. Usually no more than seventy-two hours in total."

Seventy-two hours. He'd have emails to send, a few assignments would be late. But there was no doubt in his mind he'd turn his world upside down if Stiles needed him to. It was part of what it meant to be an alpha.

Derek looked to his unlocked door; people were constantly in and out of his room during the day. "We can't stay here," he said, already running through his packing list. "When you're up to it, we'll move to one of the heatrooms in the health center. They have suites for couples who have, you know, nowhere private of their own."

"Oh, yeah. I hadn't thought through the logistics..." Stiles said. "Yeah. Thank you."

"Don't worry. I'm here to take care of you." He pressed another gentle kiss to Stiles' neck, rubbing his cheek across Stiles' nape until his and Stiles' scents were indiscernible.

Derek had always heard from other alphas that their omega's heat was a precious time to be savored, a time of heightened desire and fertility, time for mates to strengthen their bond. As a teenager, he'd laughed at the besotted descriptions he'd found in books and later heard from his older sister. As a young adult he didn't really understand at all what it meant, for an omega to ask you to share their heat.

Derek held Stiles close, listening to the rhythmic sound of Stiles' heartbeat, and understood.

 

* * *

 

Derek's room comfortably held three people. Four people made it a little cosy. A quick headcount told him he had eight people stuffed into the room he'd thought was so spacious when he moved in.

"My room's not big enough for this," Derek announced.

Stiles came up behind him, pecking his cheek, and whispering, "I'll sit on your lap, if you want."

"Stiles," Derek said, rolling his eyes.

Stiles just winked and squeezed onto the couch between Albert and Scott.

Isaac, Boyd and Erica were cuddled on the floor in front of the TV, lying on a nest of pillows and blankets stolen from Derek's bed.

"It's game seven of the World Series," Derek said. "The common room is going to be showing it. Hell, every bar in town is going to be showing it. We don't need to watch it on my junky little TV."

Stiles scoffed. "Look, Derek, we've watched nearly every Mets game on this thing since they made the playoffs, and look what's happened! They made it to game seven of the World Series. Remember game four last series? We watched in the common room and they lost."

Erica, the resident Stats major, sat up at the bit of non-logic. "Do I need to explain correlation vs causation to you again, Stiles?"

Stiles made a childish face, and she made one right back. Derek grinned despite himself. This was his life now. He needed to accept it.

There was a sharp knock on his door, and Richard, the architect from 317, popped his head in the door.

"Hey, Derek. Oh, you're watching the game," he said, looking at the crowd with wide eyes. "I won't keep you. I just wanted to stop by and say I talked to the head of the Drama department, and it's official—I'm changing my major."

Derek walked over to shake his hand. "That's great, Rich. Congratulations!"

"Yeah, I just need to tell my parents now," he said with a chuckle. "But seriously, thanks for helping me work that out."

"No problem, man. I didn't do anything." He didn't, not really. He was just an ear for Richard when he was having a few rough nights. Maybe he set up the coffee meeting with a few drama students he knew, so Richard could ask some questions. It hadn't been anything.

His gaze darted over to Stiles, who was watching him with a grin on his face that said he was listening to every word.

"Anyway, enjoy the game. Go Royals!"

The unified shouts of indignation set Richard off in a roar of laughter, and Derek had to shoo him out the door before anyone got off the couch.  
"We need chips!" Stiles said, getting up to rifle through the shopping bag on Derek's stripped bed. He tossed a large bag to the crew on the floor, then a bag for the crew on the couch. At the last minute he pulled out a single-serve bag for Albert.

Albert caught it, his face lighting up as he saw he didn't need to eat from a bag other people had put their hands in. "You're the best," he said, getting up to sit at Derek's desk chair to eat.

"I know," Stiles said, dropping a few Doritos crumbs on his shirt as he stuffed his face.

Derek stole Albert's spot on the couch next to Stiles, throwing his arm around him. He leaned in to whisper in Stiles' ear, "You're vacuuming after the game. I don't want ants."

"Whatever, dude. If the Mets win this, we'll be celebrating on every surface of this room, and I doubt you'll be complaining about crumbs."

"Oh, God," Scott whined, eyeing the desk chair Albert occupied with envy, and probably regretting that Kira had to work. "Shut up. I'm _right_ _here_."

"Everyone shut up," Boyd called out from the floor. "You assholes turned us all into Mets fans, now let us watch them win this thing."

When the Royals tied it up in the top of the ninth, the room was silent. Derek could feel the tension radiating from Stiles, and he reached out to hold his hand. They squeezed their fingers together, sharing a look, before turning back to the game.

A half hour later Derek's hand was aching from Stiles squeezing it, when finally Daniel Murphy became The Hero of Queens with a walk-off home run in the bottom of the ninth.

Derek's room erupted in cheers as the players flooded Citi field. The noise was deafening as he was pulled into hug after hug, shaking hands, and clapping backs with old and new fans, old and new friends.

His phone was ringing, probably one of his sisters. But he couldn't answer in the chaos. The crowd down the hall in the common room was just as loud, but he doubted his floor would get a noise complaint tonight, so he let it ride.

He looked at Stiles, his face bright with excitement and his scent thick and pleasing. "I'm officially declaring myself off duty, tonight."

It was something he almost never did. He loved the RA job and all its demands and expectation—everything from talking late into the night with Richard, to keeping Jackson in line, and working Albert down from whatever panic spiral he'd gotten himself into. He hadn't been sure back in September, but he understood now why he'd been offered the position in the first place.

An alpha, and all that meant, was what he was born to be.

"I'll put a note on the door to go to RA Shauna in 220 for anything," Derek said. "Just this once."

Stiles waggled his eyebrows. "Yeah?"

"I think we have plans." Derek eyed every surface of the room, thinking about all the different ways they could meet Stiles' challenge.

Stiles threw his head back with a throaty laugh. "Everyone out!" he shouted, diving at Derek and tackling him onto the unmade mattress. "My mate and I need to celebrate!"

Derek barely noticed the door shutting and the sounds of their friends heading down the hallway. Stiles paused mid-laugh, blinking in realization of what he'd just said.

"Sorry, it might be a little early to say that—"

"No," Derek said, not finding the m-word scary in the least. "No, it's just the right time."

"Yeah?" Stiles said, eyebrows raised and face aglow.

Derek met Stiles' eyes, sharing a look that he knew he'd remember forever. "Yeah."

**Author's Note:**

> Thank you for reading! You can find the authors at their respective tumblrs: [bleep0bleep](http://bleep0bleep.tumblr.com) and [marguerite26](http://marguerite26.tumblr.com) !


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